Project Abstract PGXL Technologies is developing novel urine-based tests for detecting obstructive sleep apnea (OSA) in children. Obstructive sleep apnea (OSA) is a disorder giving rise to behavioral and learning problems, including misdiagnoses as attention deficit hyperactivity disorder (ADHD) in children. The CDC estimates the prevalence of pediatric OSA in the US at 3% - around 2.3 million. An added complication is that the prevalence of primary snoring (PS) in children approaches 20%, thus physicians are challenged in differentiating OSA from PS. The ?gold standard? test for diagnosing OSA in children is polysomnography (PSG), but it is expensive (up to $1,200 per test), involves an overnight stay in a sleep laboratory, and requires the placement of numerous sensors. Parents are often unwilling ? and children too uncooperative ? to endure a PSG test. Take-home sleep devices allow patients to monitor their sleep patterns at home, but are not available to children. Thus, a simple and inexpensive urine test would fill an important and significant clinical need. A preliminary study comparing children diagnosed with OSA by polysomnography to children with PS revealed that the peptide urocortin 3 (UCN3), a stress-related biomarker, was significantly increased in the urine of children with OSA. We have an issued US patent for the use of UCN3 as a biomarker for detecting OSA and have also developed a mass spectrometry-based assay and an immunoassay to measure UCN3. To complete definitive studies validating the clinical sensitivity and specificity of using this biomarker as a diagnostic for OSA, it is necessary to have robust CLIA-validated and standardized assays - not available today. Upon completion of this Phase I project, we will have optimized a mass spectrometry assay to CLIA-validated standards including establishing preliminary reference ranges for UNC3 in urine. Successful completion of this project will position our company for a Phase II project to rigorously develop immunoassays and clinically validate the use of UCN3 as a biomarker for detection of OSA. This project is innovative in the application of a novel biomarker for detection of OSA in children and in the use of novel extraction methods for measuring UCN3. Having robust assays for detection of OSA is anticipated to have sustainable high impact in a significant and much needed clinical problem of diagnosing sleep apnea in children. This will provide a sustainable commercialization path for PGXL Technologies to develop simple and inexpensive assays for clinical laboratories by way of assay kits as well as point-of-care and other vitro diagnostics applications.